Bicomponent fibers comprising poly(ethylene terephthalate) and poly(trimethylene terephthalate) are generally known, as disclosed, for example, in U.S. Pat. Nos. 3,671,379 and 6,656,586 and in Japanese Published Patent Applications No. JP2002-180333A and JP2002-180332A, as well as in United States Published Patent Applications No. 2003/0056553 and 2003/0108740. Yarn comprising polyester fiber and cotton is disclosed in U.S. Pat. No. 6,413,631, Japanese Published Patent Application No. JP2002-115149A, and in United States Published Patent Application No. 2003/0159423 A1. However, processing these bicomponent fibers with cotton staple can be difficult and spun yarns made from these fibers in combination with cotton can have lower quality than desired. Blending of these fibers often requires reduced percentages relative to the other fiber due to deteriorating quality at increased percentage levels of bicomponent fiber. Furthermore, the processing difficulty of these fibers can limit the range of spun yarn counts that may be produced with acceptable quality.
Bicomponent fibers comprising poly(ethylene terephthalate) and poly(trimethylene terephthalate) which are better suited for processing on the cotton system are sought. High uniformity spun yarn comprising bicomponent staple fibers and cotton and having good stretch and recovery is also sought, as are stretch fabrics with uniform appearance made from cotton/polyester spun yarns.